雷公藤氯内酯醇通过激活Wnt/β-catenin通路减轻寡聚态Aβ_(1-42)诱导的神经元凋亡  

Involvement of Wnt/β-catenin signaling in tripchlorolide protecting against oligomeric β-amyloid-_(1-42)-induced neuronal apoptosis

作　　者：吴明[1,2] 朱元贵[1,2] 潘晓东[3,1,2] 林楠[1,2] 张静[1,2] 陈晓春[3,1,2] 

机构地区：[1]福建省老年医学研究所 [2]福建医科大学神经生物学研究中心,福建福州350001 [3]福建医科大学附属协和医院神经内科

出　　处：《药学学报》2010年第7期853-859,共7页Acta Pharmaceutica Sinica

基　　金：福建省自然科学基金资助项目(2009J06015);福建省卫生厅资助课题(WZZ10601);福建医科大学重大科研项目基金资助项目(09ZD002)

摘　　要：本研究从Wnt/β-catenin信号通路角度探讨雷公藤氯内酯醇(tripchlorolide,T4)对β淀粉样蛋白(β-Amyloid,Aβ)诱导神经元凋亡的保护作用及其可能机制。通过寡聚态Aβ1-42诱导原代皮层神经元凋亡,选择T4以及Wnt/β-catenin信号通路激动剂Wnt3a和抑制剂Dkk1处理神经元,分别通过MTT法、TUNEL染色和蛋白免疫印迹观察神经元存活力、细胞凋亡以及β-catenin和GSK3β及其磷酸化产物的表达水平。结果显示:寡聚态Aβ1-42可诱导皮层神经元凋亡;T4可显著提高寡聚态Aβ1-42作用后的皮层神经元生存率,减少神经元凋亡;T4可选择性降低细胞内β-catenin的磷酸化程度,稳定细胞内β-catenin水平,同时减少GSK3β及其磷酸化产物水平。结果表明,T4可通过活化Wnt/β-catenin信号通路对抗Aβ1-42的神经毒性作用,可能具有治疗阿尔茨海默病的潜在作用。This study is to explore whether the Wnt/β-catenin signaling pathway is involved in the process of tripchlorolide（T4） protecting against oligomeric Aβ1-42-induced neuronal apoptosis.Primary cultured cortical neurons were used for the experiments on day 6 or 7.The oligomeric Aβ1-42（5 μmol·L-1 for 24 h） was applied to induce neuronal apoptosis.Prior to treatment with Aβ1-42 for 24 h,the cultured neurons were pre-incubated with T4（2.5,10,and 40 nmol·L-1）,Wnt3a（Wnt signaling agonists） and Dkk1（inhibitors） for indicated time.Then the cell viability,neuronal apoptosis,and protein levels of Wnt,glycogen synthase kinase 3β（GSK3β）,β-catenin and phospho-β-catenin were measured by MTT assay,TUNEL staining and Western blotting,respectively.The result demonstrated that oligomeric Aβ1-42 induced apoptotic neuronal cell death in a time-and dose-dependent manner.Pretreatment with T4 significantly increased the neuronal cell survival and attenuated neuronal apoptosis.Moreover,oligomeric Aβ1-42-induced phosphorylation of β-catenin and GSK3β was markedly inhibited by T4.Additionally,T4 stabilized cytoplasmic β-catenin.These results indicate that tripchlorolide protects against the neurotoxicity of Aβ by regulating Wnt/β-catenin signaling pathway.This may provide insight into the clinical application of tripchlorolide to Alzheimer＇s disease.

关 键 词：阿尔茨海默病 雷公藤氯内酯醇 细胞凋亡 AΒ1-42 WNT β-catenin 

分 类 号：R963[医药卫生—微生物与生化药学]